An Ultra-High Performance Liquid Chromatography–Mass Spectrometry Method Based on Solid-Phase Extraction Developed for the Analysis of Polyphenols in Prunus Mume Sieb. et Zucc.

Abstract Background Prunus mume Sieb. et Zucc. (P. mume) is rich in various phenolic compounds; however, there is a lack of effective quality evaluation methods. Objective The aim of this study was to establish and validate a quality evaluation method that combines composition and activity to evaluate P. mume. Methods Phenolic compounds were quantified using an ultra-high performance liquid chromatography–diode array detector (UPLC–DAD) and identified using quadrupole time-of-flight mass spectrometry (UPLC–Q-TOF-MS). A solid-phase extraction (SPE) method was used for enrichment and purification. An Eclipse Plus-C18 (2.1 × 50 mm, 5 μm) column was used for separation at a flow rate of 0.25 mL/min, column temperature of 30°C, and detection wavelength of 325 nm. 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) and ferric ion-reducing antioxidant power (FRAP) assays were used to determine the antioxidant activity of P. mume. In addition, tyrosinase inhibitory activity (TIA) was verified for the first time. Results Twelve major phenolic compounds were identified, among which taxifolin and ferulic acid were first detected in P. mume. The established UPLC–DAD method exhibited a strong linear relationship (R2 = 0.9999). The limit of detection and limit of quantitation of the standard compounds were in the ranges of 0.001–0.014 ng/g and 0.009–0.048 ng/g, respectively. The method exhibited good linearity, precision, stability, and repeatability. The phenolic compound content was in the range of 0.38–75.88 mg/g. In addition, P. mume extract showed excellent ABTS•+ radical scavenging capacity (half maximal inhibitory concentration (IC50) = 108.93 ± 9.43 μg/mL), FRAP (10.23 ± 0.11 μM), and TIA (IC50 = 4.79 ± 0.08 mg/mL). Conclusion The established QC method based on composition and activity is dependable and can be used for QC of P. mume. Highlights The chromatographic analysis method is reliable and can provide a reference for QC methods for the determination of ingredients and activity in flower-based foods.